Hepatitis B virus (HBV) remains a major public health problem, with 350 million chronic carriers at risk of hepatic failure, cirrhosis and liver cancer. While a recombinant vaccine is available, it has a 5-10% failure rate, and treatment options are still limited. Progress in treatment and prevention can be expedited by a better understanding of the virus-host interactions involved in viral entry, replication, and pathogenesis and a better definition of the determinants for viral persistence versus clearance. The proposed conference is intended to gather about 200 scientists studying different aspects of HBV and related animal model viruses for joint discussions of the latest conceptual and technical advances. Held annually since 1985, the HBV meeting is the only basic science meeting on HBV and the related viruses. The primary goal of this application is to raise funds for travel grants to junior scientists. The 2004 HBV Meeting will be held in Woods Hole, MA, from Oct. 24-27, 2004. It will be organized by Drs. Jianming Hu and Fabien Zoulim. They will be assisted by a panel of expert HBV scientists serving as session chairs. Plans to involve more women and minorities in leadership positions will be emphasized again in 2004. The 11 oral sessions will include: new models and viral entry; transcription and replication; assembly and morphogenesis; regulatory proteins; HBV variants; immunology; pathogenesis; hepatitis delta virus; hepatocellular carcinoma; immunomodulation; and antiviral therapy. Each session will consist of 6 talks selected from submitted abstracts. Younger scientists will be particularly encouraged to participate in these sessions. Posters for each of the topics will be presented in two poster sessions. In addition, a workshop will focus on approaches to clearing chronic HBV infections, which necessitates advances in all areas of HBV research. Finally, two leading scientists from outside the HBV field will deliver keynote addresses: one on structural virology, a topic that remains to be fully addressed for HBV; the other on retroviruses, which are related to HBV, a pararetrovirus. [unreadable] [unreadable] [unreadable]